ROME (AP) -- Lawyers for Premier Silvio Berlusconi are confirming that he is under investigation in a prostitution case they call "absurd and groundless."

Nicolo Ghedini and Piero Longo said the probe represented a "very serious interference in the prime minister's private life." They said the allegations "have already been refuted by all witnesses and people directly involved."

Italy's leading newspaper reported Friday that Berlusconi is under investigation in a prostitution case involving a then-17-year-old Moroccan girl. Corriere della Sera said the 74-year-old premier is suspected of having sex with the minor and then abusing his power in trying to cover up the encounters with the girl.